The present invention relates to a frozen confection dispensing apparatus. Furthermore, the present invention relates to a system for safe removal of an empty collapsible container in a frozen confection dispensing apparatus.
When a frozen confection dispensing apparatus as described in U.S. Pat. No. 5,048,734 is being operated, air pressure is used to extrude a frozen confection through a discharge tube (dispensing spigot) by compressing or collapsing a collapsible container in which the confection is held. The means for supplying air pressure is generally an air compressor in series with a manual air valve that allows pressurized air via a nozzle into a closed compartment (pneumatic cylinder) that contains a piston, the collapsible container holding the frozen confection, and a valvable discharge tube including a spigot and plunger.
In normal operation, the closed compartment is pressurized with air from about 10 to 60 psi. This pressure is well within the safe working limits of the apparatus during product discharge as well as the periods between product dispensing. However, to change a collapsible container when it becomes empty or to work on or to inspect the interior of the closed compartment, the pressurized air in the closed compartment must first be vented to atmosphere. This is necessary to prevent the possible rapid expansion of air that would result from opening the closed compartment while still pressurized above atmospheric pressure.
In prior art teachings, for example, the opening of the closed compartment was facilitated by closing a manual air valve situated in the air line between the air compressor and the closed compartment which cut off the high pressure air means to the closed compartment. To relieve the pressure above atmospheric pressure contained in the closed compartment, the closed compartment would then have to be tilted forward by means of a supplied mechanical pivot mechanism effectively disconnecting the closed compartment from the nozzle of the high pressure air means and venting all the high pressure air contained in the closed compartment to atmosphere via the opening left by the displaced nozzle. This allowed safe opening of the closed compartment to change a collapsible container or to inspect the interior of the closed compartment.
The major fault of this system was that operators having this duty to change a collapsible container, or those interested in inspection of the interior of the closed compartment, would from time to time neglect to pull the closed compartments forward to vent the system, thus failing to relieve the high pressure air down to atmospheric pressure. This action often resulted in product losses resulting in excessive cleanup and repair.
This invention solves the problems encountered in prior art apparatuses and provides for a system and method to automatically relieve the high pressure contained in the closed compartment when the closed compartment is opened.